def decode_grammar(self, P):
g=SubGrammar(self.G)
vd = VaultDistribution()
iterp = iter(P)
stack = ['G']
done = []
while stack:
head = stack.pop()
assert head not in done
done.append(head)
p = iterp.next()
n = vd.decode_vault_size(head, p)
#print "RuleSizeDecoding:", head, n
t_set = []
for x in range(n):
rhs = self.decode(head, iterp.next())
#print "Decoding:", stack, head, '==>', rhs
if rhs != '__totoal__':
r = filter(lambda x: x not in done+stack,
self.G.get_actual_NonTlist(head, rhs))
if r:
for x in r:
if (x not in t_set):
t_set.append(x)
g.add_rule(head, rhs)
t_set.reverse()
stack.extend(t_set)
g.finalize() # fixes the freq and some other book keepings
return g
